html - ionic: how to change the size of FAB icon -

i new cross-platform dev. struggling changing size of fab. have now:

<ion-fab center middle> <button ion-fab color="blue" class="fabstartbtn"><ion-icon  name="start">start</ion-icon></button> </ion-fab>    .fabstartbtn { font-size: 72px; } 

but size still same. how can access button attribute? tried id, name, #name, :before - didn't work.

try use this:

<ion-fab center bottom>   <button ion-fab mini><ion-icon name="add"></ion-icon></button> </ion-fab> 

if use mini attribute can modify size this:

.fab[mini] {     margin: 8px;     width: 40px;     height: 40px;     line-height: 40px; } 

if modify class can make fab button bigger or smaller.